Developmental Orthopedic Disease in Foals

that blood flow may be impaired to the affected sites in the growing bone creating pockets of dead tissue which may eventually become detached from the bone and migrate into the joint The nutritional regime of the growing horse is also very important as is the rate of that growth 
In horses the development of OC lesions is likely to happen in the first few months of life but remedial treatment such as diet can facilitate the correction of defects providing they are introduced soon enough The period of growth between six months to 
one year of age is known to be especially significant in terms of correcting early stage OC bone lesions through diet and feeding regime changes that facilitate slow consistent growth Compensatory growth in foals that have suffered growth setbacks due to management or health issues can be rapid and may result in the development of OC lesions Lesions that are not detected until after 12 months of age tend to be less responsive to diet changes but surgery to remove bone fragments may be appropriate for some of these horses 
Energy and the Relationship to Hormonal Control
The impact of energy provided by feed on the development of OS and potentially DOD is a subject of great interest to scientists The research is not conclusive but it does suggest that young horses fed experimental diets high in starch and sugar from very early in life are more likely to have high plasma insulin and potentially be insulin resistant 
Consistently highcirculating insulin has a cascade of effects on other hormones in the foals body including the growth hormone insulinlike growth factor 1 IGF1 and important thyroid hormones Research suggests that high levels of plasma insulin in the foal may delay the maturation of the chondrocytes thereby delaying the onset of the ossification or mineralization of the young bone Delays such as this could be why we see DOD in some foals 
Protein content and quality in the diet is not usually an issue in the preweaned foal Neither high protein diets 126 percent of National Research Council NRC recommendations for growing foals nor low protein diets 9 percent protein of the NRC minimum protein recommendation of approximately 13 percent fed in research trials conducted on growing foals had a significant impact on the incidence of DOD Very low protein diets in growing foals did depress their growth rates feed intake and feed